Film preserving package



, 066 ZGSO! SHEPPARD ET s E- 937.. 1 l l May GE ACKA PRES'ERVING P FILM1933 .led oct. 31' F1 @hm www me Patented May 11,' 1937 FILM rnEsEavlnGrscmscr:v

Samuel E. Sheppard and John J. Schmitt, Rochest'er, N. Y., assignors, by-mesne assignments, to Eastman Kodak Company, Jersey Gity, N. J., acorporation of New Jersey Application October 31, 1933, Serial No.696,012

(ci. 20s-sez) 6 Claims.

This invention relates to' photography and more-particularly topackaging photographica'lly light-sensitive film toprevent-deterioration.

It has been common practice to use wooden cores for winding convolutionsof iiim or convolution of lm and film backing paper for photographicuse. The coils of film so wound are ordinarily sold in cans or othersubstantially moistureproof containers which preserve the ilm from thevusual climatic changes vto which it is subjected.

The use of such wooden cores has som'e advantages and somedisadvantages. One of the advantages is that a wooden core may absorband give off a certain amount of moisture which ls desirable but at thesame time the wooden core is liable to give off vaporswhich react on thephotographic lm and cause it to become fogged. This is due to theliberation of volatile peroxides, chiefly hydrogen peroxide.

In Patent No. 1,921,950, Samuel E. Sheppard. August 8, 1933, non-foggingphotographic packing materials are considered and in this patent variousmethods of treating woodencores to prevent them from giving oi foggingmaterials are disclosed.

In order to overcome the above-mentioned and other diiculties due to theuse of wooden cores, metallic cores are coming into use, these havingmany advantages over the wooden cores. It has been found, however, thatwith the use of a metallic support for the film, there is a greatertendency for water vapor to condense due to the temperature changes andform liquid drops of water which are responsible for the so-calledmoisture spots and moisture mottle which ruins I film.

Our present invention is particularly directed to a means for overcomingor at least minimizingv the tendency to condensation. To obtain thedesired results we fill the metal core or place in the film package asubstance of high moisture regain which will both take upwater vaporwith fair velocity and also give it up. Thus, such a substance willserve as a stabilizing material and f will prevent the-formation ofliquid water drops due to condensation. y

It is obvious that it is not highly important as to the location of thestabilizing material ln the film package, except that it is, of course,desirable to have such material in a position in which it can readilyperformthe desired function.

Coming now to the drawing wherein like reference characters denote likeparts throughout:

Figure 1 is a perspective view partially in section showing a filmpackage constructed in accordance with and embodying a preferred form ofour invention.

4Figure 2 is a perspective view of a film core which may be used inaccordance with a dliletent embodiment of our invention.

Figure 3 is a section through still another type of lm core suited foruse with our invention.

Figure 4 is a. sectionV through a film package suitable for use with theordinary hand camera Iiilm cartridges, but equipped for use with ourinvention, and

Figure 5 is a section through a lm package constructed' in accordancewith still another embodiment of our invention.

In Figure 1 we have illustrated a usual type i of lm package in whichthe film F is supported on a spool which consists of a cylindrical hubmember I and Bange members 2 for protecting the edges of the film. Suchspools are well known.

However, the hub member l differs from the usual hub members in having'a series of perforatlons 3 in the periphery of the hub and a series ofperforations l in the anges lying over the ends of the hub. Theseperforatlons permit the air inside the container to circulate freelythrough and around the hub. The film spool is enclosed in a canconsisting of a top member 5 and a bottom member 6 which lit togetherthrough the flanges I and B which inter-engage to form a tight joint.This joint is renderedsubstantially air-tight by means of a paster ortape 9 which may be of the usual surgeons adhesive tape so that theentire package is substantially moistureproof.

The moisture content of the room in which the lm is packed and of theilm itself determines to a largeextent the moisture conditions in theair inside of the package. However, it has been found that due totemperature changes the film given 01T.

y It is. important that the materials'used should be incapable Aofdeliquescing and liquefying however much moisture they may take up,because of course, if they should liquefy they would spoil the i'llm inthe same Way as the water drops. It is also important that 'thematerials must be chemically inert towards the nlm-that is, that theymust not give off vapors Vwhich deleteriously aiect the nlm.

We have found as suitable materials to place in the lm package thatvapor absorbing mineral gels may be used, such as silica gel. iron`oxide gels may be mixed and if desired. We have also found thatcellulosic materials may be used. vsuoli as Vwood pulp3. paper pulp,mercerlzed, washed, and dried cotton cellulose. These may be used aloneor mixed.

In the case of cellulose materials, where 'there is a possibility ofauto-oxidation and production of logging peromdes, this-may be overcomeby pretreatment with permanganate solutions as considered in the patentabovementioned-No.

In the speciiicatlon and in the claims where we use the term stabilizingmaterial, we mean any ofthe materials in the classes above referred to,or broadly a material capable of both absorbingand giving od moisture tostabilize the moisture content of the film 'package preventing theformation of waterdroplets. Such materials really transfer the moistureto and from the film as temperature conditions change and preventmoisture from condensing into drops of water.

v.as mentioned above, the stabilizing materials may be treated, ifdesired, tol prevent chemical fogging of the iilm.

It is impossible to give deiinite limits of humidity at which the nlmmay take-up or give od moisture because there are so many contributingfactors. Film, when packed, may contain quite widely varying moisturecontent. The lm may be packaged under varying conditions'o humidity.Consequently with diderent nlm packages the moisture transfer may occurat dlerent temperatures.

Referring again to the drawing, it is possible to place a loose orunsupported coil of in a container in which a small box contains thestabilizing material, or the box may be made into a hub by making itvcylindrical as shown in Figure 2 wherein the lhub consists of acylindrical periphery il perforated at i2 having a bottom i3perforated'at Il. The stabilizing materials may be introduced through acover member l5 and the film may be wound directly on the hub i i.

In accordance with Figure 3, a hub i@ is shown as having a centralopening il with perforations it and as including side walls ldperforated vat 2d. stabilizing material lil may be placed inside of theannular space' 2l' and the moisture can pass through the slots I8 and29'.

It is customary to pack nlm for cameras of l the amateur type inmoistureproof metal containers such as lead or composition tubes. Figure4 we have illustrated such a tube at 25, this tube supportingconvolutions of film or nlm and backing paper 26 wound upon -a hub 2l onthe ends of which there are flanges 28. The hub may be perforated at 29so that the stabilizing material lil may absorb and may give olimoisture to the lm 26.

Figure shows another type of container which -may be used to carryoutour invention. In this case the lrn 3B is wound on an imperforatecylindrical member 3l which may t loosely over a box 32 which isperforated at 33 and which contains a stabilizing material l0. Forconvenience, this box opens on the outside of the container whichconsists of two parts 84 and 35 which may be sealed together in anysuitable manner. A

screw cap or door 3S permits the stabilizing material to be introducedinto the package.

protector.

aosaoee `gels, or alumina oxide gels. Different mineral 'While it is notnecessary tor the lm package to be absolutely moistureproof, bestresults can be obtained .with a stabilizing material, in accordance withour invention, by having the package nsubstantially moisture-proofbecause the condition of the lmcan be beter controlled.

We are aware that iilm has been packed in containers in which anabsorbent material may be partially saturated with a liquid capable ofmaintaining the air in the case in a moist condition. Such containersare frequently used for developed which is not so susceptible tomoisture spots and which becomes very dry and brittlc through passingthrough the light beam of a Howevenpsuch a humidifying device is totallyunsuitable for unexposed light-sensitive photographic film.

We are also aware that the use of calcium `chloride or other moistureabsorbing substances has been suggested particularly for use withcertain types of light-sensitive photographic paper which must be keptextremely dry before um.

obviously such a material is unautea for and would not accomplishapplicants purpose.

In one case the sole object is to supply moisture to a film to preventit from becoming dried out and brittle, and in the other case the objectis solely to keep the photographic paper as dry as possible.

Our ,present invention is not for either oi these purposes.` We do notwish to moisten dry film or keep sensitive material dry. Our inventionis stabilizing the moisture content of a nlm package and preventingmoisture spots on lm byy transferring moisture back and forth, iftemperature conditions require it, between a moisfrom the followinggroup, silica gel, iron'oxlde gel, alumina gel.

3. A photographic film package including photographically lightsensitive material enclosed with a moisture-stabilizing materialconsisting essentially of silica gel.

4. A photographic lm package including photographically lightv sensitivematerial enclosed with a moisture-stabilizing material consistingessentially of iron oxide gel.

5.- A photographic film package including photographically lightsensitive material enclosed with a moisture-stabilizing materialconsisting essentially of aluminum gel.

6. A photographic nlm package including photographically light sensitivematerial enclosed with a moisture-stabilizing material consistingessentially of a mixture of mineral gels having the properties of givingup and absorbing mois--l ture;

SAMUEL E. sHEPPAaD. JOHN J. scm/irma4

